Variable volume distributor adapted to provide uniform throw



United States Patent [72] inventors Joseph W.Spradling;

John F. Newell, Madison, Wisconsin [21] AppLNo. 699,668 [22] Filed Jan.22, 1968 [45] Patented Nov. 3, 1970 [73] Assignee Wehr Corporation Milwaukee, Wisconsin a corporation of Wisconsin [54] VARIABLE VOLUME DISTRIBUTOR ADAPTED TO PROVIDE UNIFORM THROW 7 Claims, 3 Drawing Figs.

[52] U.S.Cl 98/40, 236/49 [51] Int.Cl. F241 13/06 [50] Field of Search 98/40, 40(D), 40(3), 41; 23 6/49 [56] References Cited UNITED STATES PATENTS 2,367,104 l/1945 Demuth 98/40 2,701,998 2/1955 Wulie 98/40 2,749,044 6/1956 Chace 236/49 2,790,372 4/1957 Cooper 98/41 3,299,797 1/1967 Dry..... 98/41X 3,363,536 1/1968 Dean 98/41 3,383,999 5/1968 Fragnitoetal 236/49 FOREIGN PATENTS 757,654 9/1956 GreatBritain 913/40 Primary Examiner-William E. Wayner A? Cow m N' r Peas-swag Ale Sat/me Attorneys-John W. Michael, Gerrit D. Foster, Bayard H.

Michael, Paul R. Puerner, Joseph A. Gemignani, Andrew 0. Riteris and Spencer B. Michael ABSTRACT: A distributor unit is provided which opens into a room, or other area which is to be supplied by conditioned air, through an outlet in the ceiling or one of the other room walls. The volume of conditioned air discharged through the unit outlet is varied by varying the effective area of the outlet opening into the room in direct relationship with the desired variation of volume flow into the room. This arrangement, when coupled with a constant pressure source of air, maintains a relatively uniform discharge velocity through the outlet and thus a substantially uniform throw of delivered air into the room. Structurally, a damper-deflector (hereinafter referred to as a damper) is supported at the outlet and is movable vertically to assume selectively a position closed on the outlet, a position spaced outwardly from and fully opening the outlet, or any position in between these two extreme positions. Throughout its range of movement the damper is in general alignment with the outlet to interrupt air flow and direct flow horizontally over the damper periphery and between the damper and the margin of the outlet. As the demand for conditioned air increases, the damper moves away from the outlet to increase the volume of air being discharged with the effective outlet opening being increased in direct relation to the increased volume so that the discharge velocity remains substantially constant. Similarly a decrease in demand is met by the damper moving toward the outlet to correspondingly decrease the outlet opening and volume so that again the volume is changed but without varying discharge velocity.

The damper is preferably enclosed by an imperforate horizontal plate spaced from the outlet and a'perforated cylindrical member extending around the damper and on which the imperforate plate is suspended. The damper directs air into and through the perforated member.

- VARIABLE VOLUME DISTRIBUTOR ADAPTEI) TO PROVIDE UNIFORM THROW BACKGROIND OF INVENTION l. Field of Invention This invention relates to distribution systems for conditioned air and the like and, more particularly, relates to a distribution unit for controlling discharge into an area being supplied with the conditioned air.

2. Description of Prior Art Various types of distribution systems and distribution units for controlling discharge of conditioned air are known. For example, one type mixes hot andcoldair in requisite amounts to achieve a desired temperature, these types generally discharge a constant volume of air into a room and achieve temperature regulation through adjustment of the temperature of the discharge air. Another type discharges air having a particular temperature condition (hot or cold) and achieves temperature regulation by adjusting the volume of air discharged, these types have generally exhibited the shortcoming that, as the volume of air discharged is varied, the velocity of air discharge fluctuates thereby producing undesirable drafts and areas of stagnant air. This invention is concerned with this later type and the problem of fluctuation of air discharge velocity with volume adjustment.

S U MMARY OF INVENTION In accordance with this invention a distributor unit is provided which is adapted to vary the volume of discharge to meet a change in demand by varying the effective outlet opening in direct relation to the change .in volume to thereby maintain a relatively constant discharge velocity. The distributor unit includes a damper adapted to be moved relative to the outlet opening in accordance with the change in demand. The distributor unit is preferably connected to the ceiling of a room being supplied with conditioned air and the damper is movable outwardly from a position closed on said outlet to increase the effective outlet opening, the damper being in general alignment with the outlet opening throughout the range of damper movement. Movement of the damper varies defining points of discharge of the air into the room through the ceiling. One such distribution unit is illustrated in FIG. 1 and it will be appreciated that one or more distribution units of this type can be provided in the ceiling depending upon the size of the room and the amount of air to be delivered to the room.

the amount of obstruction to flow from the distribution unit and thereby varies the effective outlet opening. Damper movement is adapted to be controlled in accordance with the temperature condition of the room being supplied, the damper moving to increase and decrease the effective outlet opening as the demand for conditioned air in the room increases and decreases, respectively. This varies the outlet opening directly as the volume is varied to thereby maintain a substantially uniform discharge velocity and uniform throw into the room.

DESCRIPTION OF DRAWINGS FIG. 'I is a generally schematic illustration of a system incorporating this invention and associated with a room;

FIG. 2 is a section view through the distributor unit illustrating the two extreme positions of the damper; and

FIG. 3 is top plan view of the'distributor unit.

DESCRIPTION OF PREFERRED EMBODIMENT This invention will be discussed in connection with a ceiling installation adapted to discharge condition air into a room with a horizontal throw, but it will be appreciated that it is not limited to such an installation. Therefore, the terms horizontal and vertical as used herein should not be considered as limitations on the scope of the invention. Furthermore, this invention is not necessarily limited to handling of conditioned air.

A portion of the ceiling l0 and one wall 12 of a room are illustrated in FIG. I. The exact structural details of the room walls are not critical tovthis invention and for that reason they will not be described. In a conventional manner, a network of ducts is provided within ceiling l0, portions 14 and 16 of the ducts have been illustrated in FIG. 1, and is effective to deliver air from a constant pressure source 18 to distribution units With reference to FIGS. 2 and 3, the distribution unit 20, which is also commonly referred as a diffuser, includes a bonnet 22 disposed within the ceiling structure. The bonnet is generally conical defining an inlet opening 24, an outlet opening 26 and a passage between the inlet and outlet. The neck 28 defining the inlet opening is suitably attached to duct 14 so that air can be delivered into the distribution unit. The bonnet includes a flange 30 extending around the periphery or margin of outlet 26 and is connected in the ceiling by screws 32 which pass through the flange and are anchored in the ceiling structure. Outlet 26 is generally flush with the ceiling surface and is positioned in a horizontal plane.

Air is directed through the bonnet as illustrated by the arrows in FIG. 2 and this invention is concerned with supplying conditioned air to the room and varying the volume of the air supplied in accordance with the temperature demand in the room. The description will proceed as though in an air conditioning environment with cool air being supplied to the room but it will be appreciated that this invention could be used to control a heating operation with hot air being supplied to the room. Variation in the amount of cooling air being supplied to the room can be achieved by either increasing or decreasing the volume of air delivered. One of the problems which has been encountered in such systems is that when the volume of air delivered is varied, the velocity of the air being discharged from the distributor unit also varies. Variation in discharge velocity causes the horizontal throw of the air into the room to fluctuate and this results in uncomfortable drafts and/or stagnant areas of air within the room. The distributor unit constructed in accordance with this invention achieves temperature control by varying the volume of air delivered to the room and does so while maintaining a constant throw into the room. To this end, the distributor unit includes'a damper 34 supported at the distributor outlet 26. The damper is movable relative to the outlet to effect the change in flow volume required to achieve a desired temperature change.

More specifically, outlet opening 26 is circular and the damper is in the form of a circular disc having an extension which is at least equal to that of the outlet opening. The damper is supported by motor 36 such that it overlies and is in alignment with outlet opening 26 The structural support-for motor 36 will be described before describing the function of the motor in varying the position of damper 34. The motor is supported in the bonnet by spider frame 38 including three struts 40, 42 and '44 each having an end suitably anchored on tabs 46, 48 and 50 formed from the bonnet. The inner ends of struts 40, 42 and 44 are generally L- shaped each having a vertical leg 52, 54 and 56. A Y-shaped strut 58 has three legs 60, 62 and 64 each welded to a respective one of legs 52, 54 and 56. The Y-shaped strut engages the top 66 of the motor and brackets 68, 70 and 72 attached to struts 40, 42 and 44 by means of screws 74, engage the underside of a shoulder 76 on the motor to securely hold the motor in the bonnet.

In the illustrated embodiment, motor 36 is a conventional air motor having an operating rod 76 connected to damper 34 by means of threaded connection of nut 78 on the end of rod 76. Motor 36 includes an air operated piston (not shown) which when exposed to air pressure, in a manner to be described hereinafter, moves rod 76 through a particular range of movement or stroke. The damper is connected to the rod and moves therewith through that range of movement and with respect to outlet opening 26. When rod 76 is retracted within motor 36, damper 34 is engaged over outlet 26, this is illustrated by the dotted line showing a damper 34 in FIG. 2, and interrupts flow through the distributor unit. The motor can be operated to move the damper away from the outlet to open the distributor unit to flow. The full line showing of the damper 34 in FIG. 2 illustrates the damper in its full open position. The motor can also be operated to locate the damper at any position between full open and full closed. Preferably, the damper is parallel to the plane of outlet 26 and its movement toward and away from the outlet is vertical or normal to the plane of the outlet. When the damper is spaced outwardly of the outlet, thereby opening the distributor unit to flow, the damper interrupts air flow through the distributor unit and deflects the flow in a horizontal direction over the periphery of the damper and between that periphery and the margin of outlet 26. The damper functions both as a damper and a deflector. Therefore, the effective outlet opening which determines the volume of flow through the distributor unit into the room varies in accordance with the distance between the damper and the outlet opening, or in other words in accordance with the amount of obstruction to flow through the unit.

In the illustrated embodiment, motor 36 is controlled in accordance with the temperature of the room. Any number of control arrangements can be utilized. As illustrated a thermostat 80 is positioned within the room and is connected to and controls a source of air pressure 82. Source 82 is connected to motor 36 through tubing 84. The thermostat senses the temperature of the room and operates air source 82 to vary the air pressure exerted on motor 36 and thereby control operation of the motor. For example, where distributor unit 20 is furnishing cool air to a room, should thermostat 80 sense a condition requiring full cooling, it operates air source 82 to supply air at p.s.i.g. to the motor which moves the damper to the full open position. in contrast, should thermostat 80 sense a condition requiring no cooling, the motor is exposed to zero p.s.i.g. which permits the rod to be retracted within the motor housing moving damper 34 to its position closed on outlet 26 to interrupt airflow. Retraction of the rod into the motor housing can be achieved through a suitable spring arrangement and against which the pressure acts. ln normal operation the damper will assume some position between the full open and full closed positions and .will modulate from that position to meet changes in temperature demand within theroom.

This arrangement, when coupled with the constant pressure source of air, is capable of varying the volume of air being supplied to the room without altering the horizontal throw of that air. More specifically, as increased cooling is called for by the thermostat, damper 34 is moved away from the outlet to increase the effective area of the outlet opening, i.e. this varies the opening into the room through which air passes. This results in a greater volume of flow through the outlet but the greater volume is also through a relatively larger effective outlet opening so that the velocity of discharge remains substantially the same as before the change occurred. Since the discharge velocity remains uniform the throw of the air into the room also remains uniform. Similarly, if decreased cooling is called for the damper moves toward the outlet to compensate for the reduced demand in the room. This reduces the volume of air to correspondingly reduce the cooling in the room but the lower volume is being discharged through a smaller effective outlet opening so that the discharge velocity remains constant and the velocity of discharge into the room is not changed. Preferably, the relationship between the motor control and the motor issuch that the effective outlet opening varies directly and linearly with the demand to thereby meet the changes in the demand while maintaining discharge velocity and horizontal throw constant.

The outlet of the distributor is flush with the ceiling but the damper 34 projects outwardly of the distributor unit into the room. Preferably, the damper is enclosed by housing 86. This housing includes an imperforate plate 88 spaced outwardly of the damper and outlet. A perforated cylindrical wall 90 is connected to a lip 92 on plate 88 and includes a flange 94 at its upper end. Flange 94 is connected to flange 30 of bonnet 22 by screws 32. Preferably, U-shaped clips 96 are provided at each point of connection and fit over flange 30. An annular edge .98 is also connected in the distributor unit by screws 32 and has an extension beyond flanges 30 and 94. Annular edge 98 is a cover ring which is exposed on the ceiling and covers the joint between the distributor unit and the ceiling.

Imperforate plate 88 overlies both damper 34 and outlet 26 to cooperate in interrupting air flow through the distributor unit. The perforated member 90 completes the enclosure for the damper while permitting relatively free flow of air into the room, the air being deflected off of damper 34 through perforated member 90.

Although but one embodiment of the present invention has been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

We claim:

1. A variable volume air distribution arrangement in combination with a generally constant pressure source of air and arranged to discharge air having a preselected temperature condition into a room, said air distribution arrangement comprising:

a distributor unit assembly connected to a wall of said room and including:

means defining a passage having an outlet into said room;

a damper;

means supporting said damper at said outlet and for movement relative to said outlet between a first position closing said outlet to airflow and a second position generally opening said outlet to airflow so that said damper interrupts air being discharged through said outlet;

operating means connected to said damper for moving said damper to assume selectively said first position, said second position and any position therebetween to thereby vary the volume of air discharged into said room and regulate the temperature in said room;

means connecting said passage to said constant pressure source for delivering air to said passage for discharge through said outlet;

enclosure means connected at and projecting downstream from said outlet, said enclosure means enclosing said damper and including an outer enclosure member spaced from said outlet and extending generally over said outlet and damper, said enclosure means also including substantially open means connected in said distributor unit extending around said damper and supporting said outer enclosure member in said distributor unit assembly while permitting flow from said distributor unit assembly into said room; and

control means responsive to the temperature condition within said room and connected to and controlling said operating means, said control means operative in response to a decrease in the demand for said air to actuate said operating means to move said damper toward said first position to reduce the volume of air being discharged through said outlet and further operative in response to an increase in the demand for said air to move said damper toward said second position to increase the volume of air being discharged through said outlet so that the effective area of said outlet opening into said room varies directly with the demand for air volume and variable volume distribution is achieved while maintaining a substantially uniform discharge velocity of air into said room.

2. The system of claim 1 wherein:

said damper is spaced downstream of said outlet when in said second position and is in registry on said outlet when in said first position;

said damper having an extension generally corresponding to that of said outlet; and

said support means for said damper supporting said damper for movement generally normal to said outlet so that said damper interrupts airflow through said outlet and directs airflow over the periphery of said damper generally between said damper periphery and the outlet margin; 3. A distributor unit adapted to provide variable volume discharge into an area with a substantially uniform throw, said distributor unit comprising, in combination:

means defining an outlet; means for directing flow to said outlet; damper means positioned I downstream of said outlet and having an extension generally overlying said outlet;

operating means connected to said damper means and supporting said damper means overlying said outlet and for movement of said damper means generally normal to and toward and away from said outlet;

said operating means operative to move said damper means to assume a first position generally closing said outlet to flow, a second position spaced from and opening said outlet to flow, and any position between said first and second positions;

said operating means including a movable member connected to said damper means and drive means for moving said movable member to assume positions within a preselected range of movement to move said damper means between said first and second positions;

means connecting said operating means in said unit whereby said damper means, when spaced from said first position, interrupts discharge flow through said outlet and redirects flow over the periphery of said damper means generally between said damper means and the margin of said outlet and movement of said damper means relative to said outlet to vary the volume of discharge through said outlet also varies the effective opening of the outlet and the volume of discharge is varied while a substantially uniform discharge velocity of air is maintained; and

enclosure means connected at and projecting downstream from said outlet, said enclosure means including an outer enclosure member spaced from said outlet and extending generally over said outlet and damper means and a perforated, generally cylindrical member connected between said outer enclosure member and said outlet and surrounding said damper means.

4. A variable volume air distribution arrangement in combination with a generally constant pressure source of air and arranged to discharge air having a preselected temperature condition into a room, said air distribution arrangement comprising:

a distributor unit assembly connected to the ceiling of said room and including:

means defining a passage having an outlet into said room and with said outlet being in a generally horizontal plane;

a damper;

means supporting said damper for movement generally normal to said outlet between a first position closing said outlet to airflow and a second position generally opening said outlet to airflow, said damper being spaced downstream of said outlet when in said second position and having a generally horizontal orientation, said damper overlying and generally coextensive with said outlet, whereby said distributor unit assembly is adapted to be positioned with said damper extending into said room and operative to interrupt airflow through said outlet and direct said airflow over the periphery of said damper generally between said damper periphery and the outlet margin;

operating means connected to said damper for moving said damper to assume selectively said first position, said second position and any position therebetween to thereby vary the volume of air discharged into said room and regulate the temperature in said room; and

means connecting said passage to said constant pressure source for delivering air to said passage for discharge through said outlet; control means responsive to the temperature condition within said room and connected to and controlling said operating means, said control means operative in response to a decrease in the demand for said air to actuate said operating means to move said damper toward said first position to-reduce the volume of air being discharged through said outlet and further operative in response to an increase in the demand for said air to move said damper toward said second position to increase the volume of air being discharged through said outlet so that the effective area of said outlet opening into said room varies directly with the demand for air volume and variable volume distribution is achieved while maintaining a substantially uniform discharge velocity of air into said room; and

enclosure means connected at and projecting downstream from said outlet, said enclosure means enclosing said damper and including:

an outer enclosure member spaced from said outlet and extending generally over said outlet and damper; and

substantially open means connected in said distributor unit assembly extending around said damper and supporting said outer enclosure member in said distributor unit assembly while permitting flow from said distributor unit assembly into said room.

5. The combination of claim 4 wherein said substantially open means comprises a perforated, generally cylindrical member connected to'and extending from said means defining said passage and said outer enclosure member.

6'. The combination of claim 4 wherein said control means comprises a thermostat in said room, and said operating means has a range of movement to move said damper between said first and second positions,'said operating means operative to position said damper within said range of movement in accordance with the signal from said thermostat.

7. The combination of claim 4 wherein said outer enclosure member is imperforate. 

